package com.edu.mapper;

import com.edu.bean.Grade;

import java.util.List;
import java.util.Map;

public interface GradeMapper {

    Grade selectGradeById(int gradeId);

    Map<String,Object> selectGradeById2(int gradeId);

    List<Grade> selectAllGrade();

    //查询每个班级的信息和该班的总人数
    List<Map<String,Object>> selectAllGrade2();

    //查询班级的数量
    int selectGradeNum();

}
